When there are a large number of contacts on a board, a certain amount of force is necessary for insertion and extraction of the board into and out of an edge connector. Attempts have already been made to reduce, or even to eliminate this force.
Connectors in which this force for insertion or extraction is eliminated are already known. One type of known connector includes two arms which are hinged at one of their ends, at least one of the arms being provided with contacts; a contact support member such as for example a male connector or a printed circuit board is introduced between the two arms which are subsequently brought together. There is no provision for guiding the insertion or extraction of the contact support member in such a connector, and above all it is difficult to obtain identical pressure on all the contacts which are spaced at intervals along one arm.
A connector in the shape of a U provided with contacts inside the U, on each one of the arms is also known. Such a connector includes means for displacing the contacts to the point where they meet with the contact support member which had been introduced between the arms of the U through the open end of the said U. In this type of connector it is not possible to insert a contact support member from one of its ends, said contact support member having to slide between the arms.
In the connector having two hinged arms it is possible to carry out introduction through the open end, but the opening up of the hinged arms which is necessary for insertion, causes this type of connector to be somewhat cumbersome and prevents its use in a rack carrying a large number of connectors.